Wyniki wyszukiwania dla: physical chemistry
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Photosensitization of TiO2 and SnO2 by Artificial Self-Assembling Mimics of the Natural Chlorosomal Bacteriochlorophylls
PublikacjaOf all known photosynthetic organisms, the green sulfur bacteria are able to survive under the lowest illumination conditions due to highly efficient photon management and exciton transport enabled by their special organelles, the chlorosomes, which consist mainly of self-assembled bacteriochlorophyll c, d, or e molecules. A challenging task is to mimic the principle of self-assembling chromophores in artificial light-harvesting...
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Characteristics of hydration water around hen egg lysozyme as the protein model in aqueous solution. FTIR spectroscopy and molecular dynamics simulation
PublikacjaW niniejszej pracy przedstawiono wyniki badań dotyczące hydratacji białka modelowego - lizozymu z jaja kurzego w roztworze wodnym. Wiodącą techniką stosowaną w badaniach była spektroskopia oscylacyjna FTIR z zastosowaniem techniki rozcieńczenia izotopowego wody półciężkiej HDO w roztworze wody zwykłej. Analiza widma HDO przy pomocy "metody widm zaburzonych" pozwoliła na wyizolowanie widma wody zaburzonej przez lizozym, a tym samym...
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Why Are Left-Handed G-Quadruplexes Scarce?
PublikacjaG-quadruplexes (G4s) are nucleic acid structures crucial for the regulation of gene expression and genome maintenance. While they hold promise as nanodevice components, achieving desired G4 folds requires understanding the interplay between stability and structural properties, like helicity. Although right-handed G4 structures dominate the experimental data, the molecular basis for this preference over left-handed helicity is unclear....
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Tuning the work function of graphite nanoparticles via edge termination
PublikacjaGraphite nanoparticles are important in energy materials applications such as lithium-ion batteries (LIBs), supercapacitors and as catalyst supports. Tuning the work function of the nanoparticles allows local control of lithiation behaviour in LIBs, and the potential of zero charge of electrocatalysts and supercapacitors. Using large scale density functional theory (DFT) calculations, we find that the surface termination of multilayer...
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Surprising Radiolytic Stability of 8‑Thiomethyladenine in an Aqueous Solution
Publikacja8-Thiomethyladenine (ASCH3), a potentially radiosensitizing modified nucleobase, has been synthesized in a reaction between 8-thioadenine and methyl iodide. Despite favorable dissociative electron attachment (DEA) characteristics, the radiolysis of an aqueous solution of ASCH3 with a dose of X-ray amounting to as much as 300 Gy leads to no effects. Nevertheless, crossed electron-molecule beam experiments in the gas phase on ASCH3...
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Raman spectroscopic study of Ni2+-DNA interactions in aqueous systems
PublikacjaMetodą ramanowskich widm różnicowych określono sposób oddziaływania jonu Ni2+ z DNA(CT) w układach wodnych. Kation Ni(II) koordynuje w pozycjach N7 guaniny (G) i adeniny (A) w powtarzających się sekwencjach GG, AA i GA cząsteczki DNA. Jednocześnie Ni2+ oddziałuje zewnątrz sferowo poprzez cząsteczki wody z grupami fosforanowymi DNA.
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Solvation of N-methylformamide by ethanol: a comparison of molecular dynamics calculations with the experimental data
PublikacjaWykonano obliczenia metodami dynamiki molekularnej dla tytułowego układu. Rezultaty porównano z uzyskanymi wcześniej wynikami pomiarów termodynamicznych oraz wnioskami z nich wyciągniętymi.
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Mechanism of Osmolyte Stabilization–Destabilization of Proteins: Experimental Evidence
PublikacjaIn this work, we investigated the influence of stabilizing (N,N,N-trimethylglycine) and destabilizing (urea) osmolytes on the hydration spheres of biomacromolecules in folded forms (trpzip-1 peptide and hen egg white lysozyme─hewl) and unfolded protein models (glycine─GLY and N-methylglycine─NMG) by means of infrared spectroscopy. GLY and NMG were clearly limited as minimal models for unfolded proteins and should be treated with...
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Surface and Trapping Energies as Predictors for the Photocatalytic Degradation of Aromatic Organic Pollutants
PublikacjaIn this study, anatase samples enclosed by the majority of three different crystal facets {0 0 1}, {1 0 0}, and {1 0 1} were successfully synthesized. These materials were further studied toward photocatalytic degradation of phenol and toluene as model organic pollutants in water and gas phases. The obtained results were analyzed concerning their surface structure, reaction type, and surface development. Moreover, the regression...
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MgPdSb─An Electron-Deficient Half-Heusler Phase
PublikacjaThe half-Heusler family consists of many semiconducting intermetallic compounds, virtually all of them having a valence electron count (VEC) of 18. We have studied an electron-deficient (VEC = 17) phase MgPdSb and its Pd-stuffed variant MgPd1.25Sb. The cubic F4̅3m crystal structure was confirmed by the Rietveld refinement of powder X-ray diffraction (XRD) data. The lattice parameter is a = 6.284 and 6.335 Å for MgPdSb and MgPd1.25Sb,...
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Hopping or Tunneling? Tailoring the Electron Transport Mechanisms through Hydrogen Bonding Geometry in the Boron-Doped Diamond Molecular Junctions
PublikacjaMechanisms of charge transport in molecular junctions involving hydrogen bonds are complex and remain mostly unclear. This study is focused on the elucidation of the electron transfer in a molecular device consisting of two boron-doped diamond interfaces bound with an aromatic linker and a hydrogen bonding surrogating molecule. The projected local density of states (PLODS) analysis coupled with transmission spectra and current−voltage...
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Core–shell excitation of isoxazole at the C, N, and O K-edges – an experimental NEXAFS and theoretical TD-DFT study
PublikacjaThe near-edge X-ray absorption fine structure (NEXAFS) spectra of the gas-phase isoxazole molecule have been measured by collecting total ion yields at the C, N, and O K-edges. The spectral structures have been interpreted using time-dependent density functional theory (TD-DFT) with the short-range corrected SRC2-BLYP exchange–correlation functional. Experimental and calculated energies of core excitations are generally in good...
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Early Stages of RNA-Mediated Conversion of Human Prions
PublikacjaPrion diseases are characterized by the conversion of prion proteins from a PrPC fold into a disease-causing PrPSC form that is self-replicating. A possible agent to trigger this conversion is polyadenosine RNA, but both mechanism and pathways of the conversion are poorly understood. Using coarse-grained molecular dynamic simulations we study the time evolution of PrPC over 600 μs. We find that both the D178N mutation and interacting...
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Linear and Nonlinear Optical Properties of Azobenzene Derivatives Modified with an (Amino)naphthalene Moiety
PublikacjaThe design of two-photon absorbing azobenzene (AB) derivatives has received much attention; however, the two-photon absorption (2PA) properties of bis-conjugated azobenzene systems are relatively less explored. Here, we present the synthesis of six azobenzene derivatives and three bisazobenzenes substituted (or not) at para position(s) with one or two amino group(s). Their linear and nonlinear absorption properties are studied...
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Systematic Water Uptake Energetics of Yttrium-Doped Barium Zirconate—A High Resolution Thermochemical Study
PublikacjaA combination of surface area analyzer and microcalorimetry was employed to investigate the in situ water uptake energetics and the mechanism of proton incorporation in yttrium-doped barium zirconate in the temperature range 200–400 °C. The BaZr1–xYxO3 solid solutions are made with variable yttrium content (x = 10, 20, and 30 mol %) by a controlled oxidant-peroxo synthesis method. The water uptake increases as the partial pressure...
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U-Turn Compression to a New Isostructural Ferrocene Phase
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Unwinding Au+···Au+ Bonded Filaments in Ligand-Supported Gold(I) Polymer under Pressure
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Pressure-Enhanced Environment Effects in Ferrocene Phases
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Superconductivity in Bismuth Pyrochlore Lattice Compounds RbBi2 and CsBi2: The Role of Relativistic Effects
PublikacjaSuperconducting properties of two bismuthide intermetallic compounds, RbBi2 and CsBi2, were studied by means of experimental measurements and ab initio calculations. We show that in both compounds, the superconductivity emerges from the pyrochlore Bi lattice and its formation is heavily influenced by relativistic effects. Based on our analysis of the effect of spin–orbit coupling on the electron–phonon coupling, we suggest a possible...
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Graph Neural Networks and Structural Information on Ionic Liquids: A Cheminformatics Study on Molecular Physicochemical Property Prediction
PublikacjaIonic liquids (ILs) provide a promising solution in many industrial applications, such as solvents, absorbents, electrolytes, catalysts, lubricants, and many others. However, due to the enormous variety of their structures, uncovering or designing those with optimal attributes requires expensive and exhaustive simulations and experiments. For these reasons, searching for an efficient theoretical tool for finding the relationship...
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Band Gap Engineering toward Semimetallic Character of Quinone-Rich Polydopamine
PublikacjaSemiconductor|melanin interfaces have received increasingly more attention in the fields of photocatalysis and applied electrochemistry because of their facile synthesis, unique electrical properties, and strong capability toward photosensitization. In this work, we describe the electropolymerization of quinone-rich polydopamine (PDA) on the surface of hydrogenated TiO2 nanotubes with enhanced photoactivity in the visible spectrum....
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Two-body dissociation of isoxazole following double photoionization – an experimental PEPIPICO and theoretical DFT and MP2 study
PublikacjaThe dissociative double photoionization of isoxazole molecules has been investigated experimentally and theoretically. The experiment has been carried out in the 27.5–36 eV photon energy range using vacuum ultraviolet (VUV) synchrotron radiation excitation combined with ion time-of-flight (TOF) spectrometry and photoelectron–photoion–photoion coincidence (PEPIPICO) technique. Five wellresolved two-body dissociation channels have...
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Molecular biaxiality determines the helical structure – infrared measurements of the molecular order in the nematic twist-bend phase of difluoro terphenyl dimer
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Anomalous Thermal Behavior of Salicylsalicylic Acid and Evidence for a Monotropic Transition to a Nematic Phase
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Soft modes of the dielectric response in the twist–bend nematic phase and identification of the transition to a nematic splay bend phase in the CBC7CB dimer
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Doping-Induced Immobile Charge Carriers in Polyazomethine: A Spectroscopic Study
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Generalization of the elastic network model for the study of large conformational changes in biomolecules
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The HAlF4 superacid fragmentation induced by an excess electron attachment
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Polysaccharide–Protein Complexes in a Coarse-Grained Model
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Dissociative electron attachment to gas phase thiothymine: experimental and theoretical approaches
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Mechanism for Damage to DNA by Low-Energy Electrons
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New D−π–D−π–A Systems Based on Phenothiazine Derivatives with Imidazole Structures for Photovoltaics
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Adaptive resolution simulation of liquid para-hydrogen: testing the robustness of the quantum-classical adaptive coupling
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Oxidizing CO2 with superhalogens
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The quantum free energy barrier for hydrogen vacancy diffusion in Na3AlH6
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Nanomechanical Stability of Aβ Tetramers and Fibril-like Structures: Molecular Dynamics Simulations
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Dissociative electron attachment to HGaF4 Lewis–Brønsted superacid
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Mechanisms of carbon monoxide hydrogenation yielding formaldehyde catalyzed by the representative strong mineral acid, H2SO4, and Lewis–Brønsted superacid, HF/AlF3
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Elastic moduli of biological fibers in a coarse-grained model: crystalline cellulose and β-amyloids
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Refinements to the Utah–Washington Mechanism of Electron Capture Dissociation
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Synthesis, Growth Mechanism, and Electrochemical Properties of Hollow Mesoporous Carbon Spheres with Controlled Diameter
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Facile Deposition of Pd Nanoparticles on Carbon Nanotube Microparticles and Their Catalytic Activity for Suzuki Coupling Reactions
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Creation of mesopores in carbon nanotubes with improved capacities for lithium ion batteries
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Dynamics and stability of icosahedral Fe–Pt nanoparticles
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Catalytic Carbonization of Chlorinated Poly(vinyl chloride) Microfibers into Carbon Microfibers with High Performance in the Photodegradation of Congo Red
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Photocatalytic Activity of TiO2 Modified with Hexafluorometallates—Fine Tuning of Redox Properties by Redox-Innocent Anions
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Spectroscopic and Spectroelectrochemical Studies on Redox Properties of Zinc Sulfide and Their Consequences on Photocatalytic Activity
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Self-Sensitized Photocatalytic Degradation of Colorless Organic Pollutants Attached to Rutile Nanorods—Experimental and Theoretical DFT+D Studies
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Combined Spectroscopic Methods of Determination of Density of Electronic States: Comparative Analysis of Diffuse Reflectance Spectroelectrochemistry and Reversed Double-Beam Photoacoustic Spectroscopy
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On the Possibility of the Amphotericin B-Sterol Complex Formation in Cholesterol- and Ergosterol-Containing Lipid Bilayers: A Molecular Dynamics Study
PublikacjaAmphotericin B (AmB) is a well-known membrane-active antibiotic that has been used to treat systemicfungal infections for more than 45 years. Therapeutic application of AmB is based on the fact that it is moreactive against ergosterol-containing membranes of fungal cells than against mammalian membranes withcholesterol. In this paper, we examine the hypothesis according to which the selectivity of the AmB's membraneaction originates...
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Visible-light-induced photocatalysis through surface Plasmon excitation of gold on titania surfaces
PublikacjaPietnascie komercyjnych probek tlenku tytanu(IV) zostalo zmodyfikowanych zlotem za pomoca fotodepozycji oraz scharakteryzowanych. Fotoaktywnosci proszkow Au/TiO2 zostaly przebadane dla fotodegradacji kwasu octowego i 2-propanolu podczas naswietlania promieniowaniem widzialnym oraz ultrafioletowym. Wykazano, ze fotokatalityczne aktywnosci scisle zaleza od wlasciwosci nanoczastek zlota i tlenku tytanu. Analizy spektrum działania...
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Electron attachment and electron iozization of acetic acid clusters embedded in helium nanodroplets
PublikacjaThe effect of incident electrons on acetic acid clusters is explored for the first time. The acetic acid clusters are formed inside liquid helium nanodroplets and both cationic and anionic productsejected in to the gas phase aredetected by mass spectrometry.
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A XAS study of a highly diluted Pt electrocatalyst operating in PEM fuel cells
PublikacjaWe present an X-ray absorption spectroscopy (XAS) study of a low Pt content catalyst layer(Pt loading 0.1 mg c2) operating at the cathode of a proton exchange membrane fuel cell(PEMFC). This catalyst is based on the use of a mesoporous inorganic matrix as a support forthe catalyst Pt nanoparticles. Due to the high Pt dilution, in situ measurements of itsstructural properties by XAS are challenging and suitable experimental strategies...
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Structural properties of hydration shell around various conformations of simple polypeptides
PublikacjaIn this paper we investigate structural properties of water within the solvation shell around the peptide core created by a well-defined conformation of polypeptide chain. The following secondary structures are investigated: linear (straight chain), and three helices PII (polyproline-like), 310, and α. We propose using the two-particle contribution to entropy as a rational measure of the water structural ordering within the solvation...
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Optimization of Parameters in Macromolecular Potential Energy Functions by Conformational Space Annealing
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Molecular Origin of Anticooperativity in Hydrophobic Association
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Optimization of the UNRES Force Field by Hierarchical Design of the Potential-Energy Landscape. 1. Tests of the Approach Using Simple Lattice Protein Models
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Modification and Optimization of the United-Residue (UNRES) Potential Energy Function for Canonical Simulations. I. Temperature Dependence of the Effective Energy Function and Tests of the Optimization Method with Single Training Proteins
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Potential of Mean Force of Association of Large Hydrophobic Particles: Toward the Nanoscale Limit
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Hydrophobic hydration and pairwise hydrophobic interaction of Lennard-Jones and Mie particles in different water models
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Development of Physics-Based Energy Functions that Predict Medium-Resolution Structures for Proteins of the α, β, and α/β Structural Classes
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Molecular Simulation Study of the Potentials of Mean Force for the Interactions between Models of Like-Charged and between Charged and Nonpolar Amino Acid Side Chains in Water
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Comment on “Molecular Origin of Anticooperativity in Hydrophobic Association”
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Optimization of the UNRES Force Field by Hierarchical Design of the Potential-Energy Landscape. 3. Use of Many Proteins in Optimization
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Global Optimization-Based Method for Deriving Intermolecular Potential Parameters for Crystals
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Reply to “Comment on ‘Crystal Structure Prediction by Global Optimization as a Tool for Evaluating Potentials: Role of the Dipole Moment Correction Term in Successful Predictions'” by B. P. van Eijck and J. Kroon
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Chemical Vapor Transport Route toward Black Phosphorus Nanobelts and Nanoribbons
PublikacjaChemical vapor transport (CVT) method is widely used for bulk black phosphorus (BP) fabrication. In this work, we demonstrate that CVT provides a route for the fabrication of BP nanoribbons and nanobelts. This method consists of a two-step procedure, including initial BP column growth using the CVT technique, followed by ultrasonic treatment and centrifugation. The obtained nanostructures preserve BP column dimensions, forming...
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Potential of Mean Force of Hydrophobic Association: Dependence on Solute Size
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Parametrization of Backbone−Electrostatic and Multibody Contributions to the UNRES Force Field for Protein-Structure Prediction from Ab Initio Energy Surfaces of Model Systems
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Optimization of the UNRES Force Field by Hierarchical Design of the Potential-Energy Landscape. 2. Off-Lattice Tests of the Method with Single Proteins
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Extension of the UNRES Coarse-Grained Force Field to Membrane Proteins in the Lipid Bilayer
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Simple Physics-Based Analytical Formulas for the Potentials of Mean Force for the Interaction of Amino Acid Side Chains in Water. 3. Calculation and Parameterization of the Potentials of Mean Force of Pairs of Identical Hydrophobic Side Chains
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Simple Physics-Based Analytical Formulas for the Potentials of Mean Force for the Interaction of Amino Acid Side Chains in Water. IV. Pairs of Different Hydrophobic Side Chains
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Reply to “Comment on ‘Molecular Origin of Anticooperativity in Hydrophobic Association'”
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Radiative lifetime of a BODIPY dye as calculated by TDDFT and EOM-CCSD methods: solvent and vibronic effects
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Energy levels in CaWO4:Tb3+ at high pressure
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Comparison of quenching mechanisms in Gd3Al5−xGaxO12:Ce3+ (x = 3 and 5) garnet phosphors by photocurrent excitation spectroscopy
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Temperature effect on the emission spectra of narrow band Mn4+phosphors for application in LEDs
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Spectroscopic properties and location of the Tb3+ and Eu3+ energy levels in Y2O2S under high hydrostatic pressure
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Properties of Charge Carrier Traps in Lu2O3:Tb,Hf Ceramic Storage Phosphors Observed by High-Pressure Spectroscopy and Photoconductivity
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Spectroscopic properties and location of the Ce3+ energy levels in Y3Al2Ga3O12 and Y3Ga5O12 at ambient and high hydrostatic pressure
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Energy Level Structure of Bi3+ in Zircon and Scheelite Polymorphs of YVO4
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Luminescence Spectra of β-SiAlON/Pr3+ Under High Hydrostatic Pressure
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Efficient Luminescence from CsPbBr3 Nanoparticles Embedded in Cs4PbBr6
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Reply to the ‘Comment on “Spectroscopic properties and location of the Ce3+ energy levels in Y3Al2Ga3O12 and Y3Ga5O12 at ambient and high hydrostatic pressure”’ by Y. Wang, M. Głowacki, M. Berkowski, A. Kamińska and A. Suchocki, Phys. Chem. Chem. Phys., 2019, 21, DOI: 10.1039/C8CP06154H
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Broadband NaK2Li[Li3SiO4]4:Ce Alkali Lithosilicate Blue Phosphors
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Study of persistent luminescence and thermoluminescence in SrSi2N2O2:Eu2+,M3+(M = Ce, Dy, and Nd)
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Spectroscopic properties of high-temperature sintered SrS:0.05%Ce3+ under high hydrostatic pressure
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Spectroscopic properties and location of the Tb3+ and Eu3+ energy levels in Y2O2S under high hydrostatic pressure
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Theoretical study of the energetics of the reactions of triplet dioxygen with hydroquinone, semiquinone, and their protonated forms: relation to the mechanism of superoxide generation in the respiratory chain = Badanie teoretyczne energii z energii reakcji dioksygenu potrójnego z wodorem, półkiną i ich formami protony: relacja z mechanizmem wytwarzania supertlenku w łańcuchu oddechowym
PublikacjaW pracy prezentujemy wyniki obliczeń kwantowych ab initio i półempirycznych energetyki reakcji redukcji jednoelektronowej tlenu trypletowego. Zaproponowaliśmy cztery możliwe mechanizmy redukcji i przeprowadziliśmy obliczenia kwantowe. Z obliczeń wynika, że najprawdopodobniejszy mechanizm reakcji wiedzie poprzez przeniesienie elektronu z anionu hydrochinonu po deprotonacji lub też z rodnika semichinonowego na tlen cząsteczkowy,...
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A low-band gap, nitrogen-modified titania visible-light photocatalyst
PublikacjaFotokatalizatory tlenku tytanu(IV) zmodyfikowanego azotem zostały zsyntetyzowane poprzez ogrzewanie wodorotlenku tytanu i mocznika w temperaturze 400ºC. Otrzymane fotokatalizatory charakteryzują się silną absorpcją w zakresie promieniowania widzialnego (400-500 nm) odznaczając się niskimi wartościami energii pasma wzbronionego (2,20 i 2,46 eV). Aktywność fotokatalityczną w świetle widzialnym potwierdzono przeprowadzając reakcję...
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Modification of titanium dioxide with platinum ions and clusters: application in photocatalysis
PublikacjaW celu polepszenia właściwości fotokatalitycznych, TiO2 (komercyjny-P25 oraz syntezowany metoda zol-żel) był domieszkowany za pomocą jonów lub klasterów [Pt3(CO)6]62- platyny. Własności fizyczne fotokatalizatorów były badane za pomocą elektronowego mikroskopu transmisyjnego (TEM), dyfraktometru rentgenowskiego (XRD) oraz analizatora powierzchni właściwej (BET). Dyfuzyjna spektrometria odbiciowa (DRS) została zastosowana w celu...
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Hydration of simple amides. FTIR spectra of HDO and theoretical studies
PublikacjaZastosowano metodę ważonych widm różnicowych do opisu hydratacji amidów w roztworach wodnych: formamidu, N-metyloformamidu, N,N-dimetyloformaidu, acetamidu, N-metyloacetamidu, N,N-dimetyloacetamidu. Narzędziem wspomagającym interpretację wyników eksperymentalnych są struktury agregatów solwatacyjnych wokół cząsteczki substancji rozpuszczonej uzyskane na podstawie obliczeń teoretycznych metodą ab initio z korelacją elektronową...
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Two-particle entropy and structural ordering in liquid water
PublikacjaEntropies of simple point charge (SPC) water were calculated over the temperature range 278-363 K using the two-particle correlation function approximation. Then, the total two-particle contribution to the entropy of the system was divided into three parts, which we call translational, configurational, and orientational. The configurational term describes the contribution to entropy, which originates from spatial distribution of...
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Structural and dynamic properties of water within the solvation layer around various conformations of the glycine-based polypeptide
PublikacjaSeveral conformations of the solvated glycine-based polypeptides were investigated using molecular dynamics simulations. Some properties of water in the neighbouring space around these molecules were investigated. It was found, that water forms a well-defined layer - the first solvation shell - around the peptide molecule, and thickness of this layer is independent of the peptide structure, and it equals to approximately 0.28 nm....
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Molar volumes and heat capacities of electrolytes and iIons in N,N-dimethylformamide
PublikacjaZmierzono gęstości i molowe pojemności elektrolitów typu 1:1 oraz o soli o wyższych liczbach ładunkowych jonów w roztworach w N,N-dimetyloformamidzie w temperaturze 25 stopni Celsjusza. W oparciu o te pomiary wyznaczono standardowe objętości molowe oraz standardowe wartości izobarycznych ciepeł molowych. Uzyskane wartości podzielono na udziały jonowe wykorzystując tetrafenyloboran tetrafenylofosfoniowy (TPTB) jako elektrolit odniesienia....
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Hydration of Carboxylate Anions: Infrared Spectroscopy of Aqueous Solutions
PublikacjaHydratacja anionów karboksylanowych w roztworach wodnych ich soli sodowych została zbadana przy wykorzystaniu spektroskopii FTIR z zastosowaniem cząsteczki HDO jako sondy molekularnej. Do wyznaczenia widm wody zaburzonej przez rozpuszczalnik wykorzystano ilościową wersję metody widm różnicowych. Widma te wykazują dwa pasma składowe przy ok. 2550 i ok. 2420 cm-1. Pasma te przypisano grupie -COO- anionu R-COO- (R = H, CH3, C2H5),...
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Systematic Study of Hydration Patterns of Phosphoric(V) Acid and Its Mono-, Di-, and Tripotassium Salts in Aqueous Solution
PublikacjaSpektroskopia oscylacyjna FTIR w zakresie drgania OD cząsteczki HDO została zastosowana do zbadania różnych form fosforanów w kolejności malejącego stopnia protonacji: H3PO4, KH2PO4, K2HPO4, K3PO4. HDO rozcieńczona izotopowo w H2O została otrzymana przez dodanie odpowiednich ilości wody ciężkiej (D2O) do roztworów w wodzie zwykłej. Do wyizolowania widm HDO zaburzonej przez substancję rozpuszczoną zastosowano metodę widm różnicowych....
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Mollecular mechanism and chemicl kinetic description of nitrobenzene liquid membrane oscillator containing benzyldimethyltetradecylammonium chloride surfactant
PublikacjaBadano oscylacje róznicy potencjału między fazami wodnymi oscylatora z nitrobenzenową membraną ciekłą zawierającego chlorek benzylodimetylotetradecyloamoniowy. Opisano chemię fizyczną tego oscylatora oraz omówiono rolę efektów hydrodynamicznych w powstawaniu oscylacji. Zaproponowano nowy mechanizm oparty na transferze masy par jonowych. Oscylacje są generowane na granicy faza akceptowa/ membrana ciekła i są spowodowane autokatalityczną...
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Effects of Urea and Trimethylamine-N-oxide on the Properties of Water and the Secondary Structure of Hen Egg White Lysozyme
PublikacjaW celu określenia sposobu hydratacji mocznika i N-tlenku trimetyloaminy, wykorzystano spektroskopię oscylacyjną FTIR. Dane eksperymentalne, otrzymane z pomiarów widm oscylacyjnych wody półciężkiej (HDO) rozcieńczonej izotopowo w wodnych roztworach badanych związków, analizowane były za pomocą "metody widm różnicowych". Strukturalno-energetyczna charakterystyka wody zaburzonej przez cząsteczki osmolitów wskazuje, że woda zaburzona...